How important is the character and temperament of a U.S. president? Those traits have the ability to shape the nation, says Pulitzer Prize-winning historian Jon Meacham.

Take, for example, Thomas Jefferson. His scholarly and pragmatic disposition still resonate more than 200 years later.

"We wouldn't be here but for Jefferson's temperament. In 1776, he was sitting in Philadelphia, writing the Declaration, the most famous press release in world history," Meacham said during a June 28, 2017, session at the Aspen Ideas Festival.

"The reason he was able to sit down and write that," Meacham said, "was he and his cohort had been conversant with, had been curious enough about the broad intellectual, cultural, economic currents of the western world of the previous two to three centuries."

He continued: "Jefferson, when he wrote arguably the most important sentence in the English language — that we are created equal and are all endowed by our creator with certain inalienable rights — a sentence that resonates unto this hour, he wasn't writing that in a vacuum."

Meacham argues that a knowledge of history "tames" presidents and is essential for a successful leader.

Listen to the full segment, "Might the Past Inform Our Future?" by clicking on the audio player above. It also features John Dickerson of CBS News.

Meacham is a presidential historian and the author of best-selling books about Presidents Andrew Jackson, Thomas Jefferson, Franklin D. Roosevelt and George H.W. Bush. "American Lion: Andrew Jackson in the White House" won the Pulitzer Prize in 2009. He's currently working on a book about James Madison.

Meacham is also a contributing writer to The New York Times Book Review, and contributing editor at Time.

John Dickerson is the author of a book about presidential campaigns, titled, "Whistlestop."